Labour’s London Mayoral candidate has said he fears his daughters “could be groomed by extremists on the internet or tricked into running off to Syria”.

Sadiq Khan, the most senior Muslim in Labour’s ranks, revealed he had grown up in south London with boys who went on to act in “terrible ways”.

And describing the mass killings in Paris as an “attack on our way of life”, Mr Khan argued people had for too long “buried our heads in the sand” over the problem and that British Muslims had a “special role to play in tackling extremism” – not because they are more responsible than other groups, but because they could be more effective in confronting it.

Speaking at a Westminster lunch for journalists, the Tooting MP said: “This fight is personal for me. Like all parents I want to know my daughters are safe. I worry that they or their friends could be groomed by extremists on the internet or tricked into running off to Syria like other children have been.

“Extremism isn’t a theoretical risk. Most British Muslims have come across someone with extremist views at some point – and so have I.

“It’s affected my personal life, my friendships, and my career. People I knew as a boy have gone on to hold extremist views, and even to act on them in terrible ways.”

He disclosed that each time he has stood as an MP he has faced a “campaign of hate” and has received police protection advice as a result.

“Extremists came and protested outside mosques in my community, handing out leaflets telling the congregation – my friends and neighbours – that voting is banned in Islam. Telling people I’ve known since I was a boy that I am destined to go to hell. They say that Muslims shouldn’t take part in democracy.”

Mr Khan, the son of a Pakistani bus driver, recalled that when he worked as a lawyer he had the “horrible” task of representing people with extremist views.

“I’ve lost count of the number of times I’ve had to challenge the hideous views of seemingly intelligent and articulate people.

“People who look and sound like normal Londoners, until they say that 9/11 was a Mossad [Israeli secret service] conspiracy, that the Jewish workers in the Twin Towers were tipped off and escaped.”

Mr Khan, who faces a close battle with Conservative Zac Goldsmith in next May’s election, also called for a “prolonged and concerted effort by us all” to tackle Britain’s “social segregation”.

He argued: “We’ve protected people’s right to live their cultural life at the expense of creating a common life. Too many British Muslims grow up without really knowing anyone from a different background, without understanding or empathising with the lives and beliefs of others.

“And too many British people have never befriended a Muslim, never worked together, never eaten together, never played sports together. As a result, too many people have formed a single identity – too often based around their religion or ethnicity.”